What Are The Chances Of Being Pregnant And Having A Negative Pregnancy Test
For most home pregnancy tests, you put the end of the test in your urine stream, dip the test in a container of urine or put several drops of urine onto the test. A few minutes later, the result appears. It's often a plus or a minus sign, the words "yes" or "no," one line or two lines, or the words "pregnant" or "not pregnant."
what are the chances of being pregnant and having a negative pregnancy test
Many home pregnancy tests claim to be 99% accurate. But home pregnancy tests differ in their ability to find a pregnancy in people who have recently missed a period. If you get a negative test result, but you still think you might be pregnant, take another test one week after your missed period or contact your health care provider.
A repeated negative pregnancy test even with a missed period typically means that you are not pregnant. A negative pregnancy test a week or more after your missed period indicates that your chance of being pregnant is less than 1-2%. A positive pregnancy test usually means that you are pregnant. However, sometimes it is possible to be pregnant even though you had a negative pregnancy test.
There are several reasons why you can have a negative pregnancy test. Maybe you miscalculated when your period was due. It's also possible you tested too soon and there is not enough hCG (the hormone that indicates pregnancy) found when you tested. You may need to wait another week and then retest.
hCG doubles about every 48 hours in early pregnancy, so a home pregnancy test that is negative on Monday could very likely be positive on Wednesday. However, if it's positive with first-morning urine, later on in the day, when the urine is more diluted, it could test negative. It is also important to remember that despite the advances in urine home pregnancy tests, blood tests are still the best at detecting early pregnancy.
The timing of a positive pregnancy test depends on implantation. If you are pregnant, a urine pregnancy test is not expected to be positive until 3-4 days after implantation (at the very earliest), which is about 10 days after ovulation/fertilization, and 4 days before the next period. About 51% of pregnant women have a positive pregnancy test two days before their next expected period.
One of the most common reasons women test negatively inaccurately is by taking a pregnancy test too early. You may be able to test as early as 10 days after ovulation, but it usually takes an average of 13-15 days after ovulation and fertilization for a pregnancy test to turn positive. Many women test too early, use a test with low sensitivity, or use the test incorrectly, which can lead to false negatives.
Other causes of false negative pregnancy tests include diluted urine, expired tests, improper testing, and ectopic pregnancy. If you test negative but have not gotten your period, make sure to take multiple tests throughout the week, and consult your healthcare provider with further questions.
Women may get a negative test result on a urine or blood pregnancy test despite being pregnant. Although many factors can contribute to a false-negative pregnancy test, the hook effect occurs when the woman has a high concentration of human chorionic gonadotropin (hCG), the pregnancy hormone. The high levels oversaturate the test and result in a false negative.
The hook effect occurs when blood, urine, or other samples contain too much of the substance that the specific pregnancy test is trying to detect. Instead of giving a positive result, the laboratory test becomes overwhelmed by the excess substance and provides a false-negative result.
Some women may consistently get negative urine and blood pregnancy test results despite being pregnant. In these situations, ultrasound tests may confirm the pregnancy. The hook effect is more common in the following situations:
Women who are experiencing symptoms of pregnancy but consistently getting negative test results from at-home urine pregnancy tests should consider speaking with a doctor. Blood tests for pregnancy may also come back negative, so the doctor may need to confirm the pregnancy with an ultrasound.
As with other diagnostic tests, doctors should make a diagnosis based on a collection of data, including symptoms, clinical findings, medical images, and laboratory testing. False-negative results from pregnancy tests can delay the confirmation of a pregnancy and, thus, prenatal care management.
Women may have symptoms of pregnancy despite consistently receiving negative test results. During the first trimester, they may feel more fatigued than usual. Some may experience nausea and vomiting, and mood swings are also common in the first trimester.
High levels of hCG can overwhelm the antibodies that pregnancy tests use. When too much hCG is present in a sample, the antibodies may fail to bind, and the test will appear negative. The hook effect may occur when levels of hCG reach 500,000 milli-international units per milliliter.
Certain medical conditions, such as cancer and pregnancy-related diseases, may cause high levels of hCG. Women having twins or triplets may also have high levels of this hormone, which can be difficult for a pregnancy test to detect.
Although the hook effect occurs very rarely, the medical implications of a false-negative result can be serious. Doctors relying on blood and urine pregnancy tests may falsely assume that the woman is not pregnant. As a result, the woman may not receive proper prenatal care until an ultrasound confirms the pregnancy.
If you think you might be pregnant and have pain or bleeding, call the doctor right away. If you are not sure if you are pregnant, see a doctor, visit a health clinic like Planned Parenthood, or use a home pregnancy test.
If you use a home pregnancy test and the results are negative but the signs point to being pregnant (like a missed or late period, breast tenderness, or feeling sick or throwing up), see a doctor or go to a health clinic. If a home pregnancy test is positive, see a health care provider as soon as possible to confirm the test and get the right care for you and your baby.
Overall, there were 11 (2.3%) positive pregnancy tests. Two initially positive urine results, when vigorously refuted by the patients, were subsequently found to be negative by confirmatory serum studies, and ordered as part of the clinician's routine work up during the same visit. These cases were counted as negative tests and are consistent with false positive rates in the literature.5
Most pregnancy tests have about the same ability to detect hCG, but their ability to show whether or not you are pregnant depends on how much hCG you are producing. If you test too early in your cycle or too close to the time you became pregnant, your placenta may not have had enough time to produce hCG. This would mean that you are pregnant but you got a negative test result.
How do you do this test? For most home pregnancy tests, you either hold a test strip in your urine stream or you collect your urine in a cup and dip your test strip into the cup. If you are pregnant, most test strips produce a colored line, but this will depend on the brand you purchased. Read the instructions for the test you bought and follow them carefully. Make sure you know how to get good results. The test usually takes only about 5 minutes.
You can improve your chances for an accurate result by using your first morning urine for the test. If you are pregnant, it will have more hCG in it than later urines. If you think you are pregnant, but your first test was negative, you can take the test again after several days. Since the amount of hCG increases rapidly when you are pregnant, you may get a positive test on later days. Some test kits come with more than one test in them to allow you to repeat the test.
Is this test similar to the one my doctor uses? The home pregnancy test and the test your doctor uses are similar in their abilities to detect hCG, however your doctor is probably more experienced in running the test. If you produce only a small amount of hCG, your doctor may not be able to detect it any better than you could. Your doctor may also use a blood test to see if you are pregnant. Finally, your doctor may have more information about you from your history, physical exam, and other tests that may give a more reliable result.
Do negative test results mean that you are not pregnant? No, there are several reasons why you could receive false negative test results. If you tested too early in your cycle, your placenta may not have had time to produce enough hCG for the test to detect. Or, you may not have waited long enough before you took this test.
If you are trying to get pregnant or have been pregnant, you probably remember the emotion and excitement you felt when waiting to see the results of a home pregnancy test. But even after you've read the results, you still may have some lingering doubt as to whether the positive or negative results you received are indeed accurate.
"If you are administering the pregnancy test after a missed period, in the majority of cases, the results of your home pregnancy test are likely to be correct," says Katherine Lessman, MD, Nebraska Medicine obstetrician-gynecologist. "Instances in which women get false negatives are usually associated with early response pregnancy tests. That's because timing is very important."
When you get pregnant, your body produces a hormone called chorionic gonadotropin, otherwise known as hCG. This hormone will increase with time after conception and can be detected in your urine. Home pregnancy tests are based on the presence of this hormone. However, hCG levels are very low for the first few weeks following conception.
"Performing an early pregnancy test within the first couple weeks after you believe you have conceived, will result in a greater likelihood that you will have a false negative, notes Dr. Lessman. In all cases, testing nine days after conception is too early."
Testing too late (after the first trimester) can also be an issue. "The hCG hormone still exists, but can become different components and may not be detected by your home pregnancy test," Dr. Lessman explains. "When there is a question, consider having a blood hCG test, which you can get at your doctor's office. This test looks for different versions of the hormone and can provide a more definitive answer." 350c69d7ab